Apparatus for particle transfer for a storage pile



Dec. 5, 1961 J. 1.. PETERSON 3,

APPARATUS FOR PARTICLE TRANSFER FOR A STORAGE PILE Fild Aug. 1, 1960 4 Sheets-Sheet 1 INVENTOR.

JB/m L. Peverson A Hys.

Dec. 5, 1961 J. L. PETERSON 3,011,658

APPARATUS FOR PARTICLE TRANSFER FOR A STORAGE PILE Filed Aug. 1, 1960 4 Sheets-Sheet 2 Afriush Dec. 5, 1961 .1. 1.. PETERSON APPARATUS FOR PARTICLE TRANSFER FOR A STORAGE FILE 4 Sheets-Sheet 3 v Filed Aug. 1, 1960 INVENTOR. J'o/m L. Peferson 74 Dec. 5, 1961 J. L. PETERSON APPARATUS FOR PARTICLE TRANSFER FOR A STORAGE FILE 4 Sheets-Sheet 4 INVENTOR. JED/7n L. Pe ferson Filed Aug. 1, 1960 Unite 3,011,658 APPARATUS FUR PARTHZLE TRANSFER FUR A STGRAGE PELE John L. Peterson, Spokane, Wash, assignor to Atlas Boiler 8.! Equipment Co., Spokane, Wash :1 corporation of Washington Filed Aug. 1, 1960, Ser. No. 46,335 Claims. (Cl. 214-410) This invention relates to a novel apparatus adapted to effect controlled volume transfer of particles from a storage pile.

Many particle materialssuch as ensilage, sawdust, vermiculite and others-are stored in piles for later removal when needed. Often a control is required so as to supply a constant volume of the particles during delivery. This is important in a sawdust burner, as an example, since a constant supply of sawdust will result in optimum burner efficiency. Such particles are normally delivered by conveyors. However, they have a tendency to bridge over the inlet to the conveyor and block the inlet, thus making volume control impossible.

According to this invention, this problem is effectively solved by providing a supporting bed for the storage pile and having recessed conveyors under the bed surface. Particles from the pile are then constantly dragged across the conveyors by a mechanical system which positively moves the particles and also clears the areas above the conveyor. It is a first object of this invention to provide such a mechanism which can be set directly on a hard surfaced support bed with a minimum of costly bearing materials.

It is another object of this invention to control the delivery rate of the mechanism by varying the speed of the dragging mechanism rather than the speed of the conveyors.

Another object of the invention is to design such an apparatus which can be adapted for use in moving particles from an enclosed pile or an open pile with equal efiiciency and which is capable of handling particles varying in size from fine elements to bulky elements.

These and further objects will be evident from a study of the following disclosure and the accompanying drawings which illustrate one preferred form of the invention. This form is merely exemplary and is not intended to detract from the full scope of the invention as set out in the annexed claims.

in the drawings:

FIGURE 1 is a top plan view of the invention with a portion of the hood broken away to show underlying r structure;

FIGURE 2 is a side view of the drag assembly with the extremities of the assembly broken away;

FIGURE 3 is a sectional view taken along line 33 in FIGURE 2;

FIGURE 4 is a sectional view taken along line 44 in FIGURE 1;

FIGURE 5 in FlGURE 1;

FIGURE 6 is a sectional view taken along line a s in IGURE 1;

FIGURE 7 is an outer view of the mechanism in FIG- URE 6 as viewed from the left hand side;

FIGURE 8 is an enlarged fragmentary view taken along a plane indicated by line 8-8 in FIGURE 4 showing an apparatus in use rotated oppositely to that shown in Fl"- URE l; and

FIGURE 9 is a diagrammatic perspective view of the apparatus in a complete conveyor assembly.

Referring now to the drawings, this invention is designed to facilitate removal and delivery of particles from is a sectional view taken along line 55 a a s states Patent: r

3,dll,658

Patented flee. 5, 1961 a storage pile to a conveyor or other delivery system. Bulk goods, such as sawdust, are normally dumped in a stack configuration which will have a conical shape unless confined by vertical Walls. According to this invention, the storage pile is to be placed on a support bed 10, preferably made of concrete and resting on the surrounding ground surface 11. Bed 10 may be formed of any suitable material, such as metals, wood or may be the ground surface itself. It should be in a horizontal plane at its upper surface and should be somewhat hard for bearing purposes, although metal wear plates may be used on soft surface installations to provide the necessary bearing support.

The bed 10 is recessed to provide sub-surface housing for a pair of cross conveyors 12, 13 which lead to a main delivery exit conveyor 14. The conveyors '12, 13 are perpendicular to conveyor 1 and are moved so as to dump their contents on o conveyor 14 at their junction. Conveyor 14 is a long conveyor and extends beyond bed 10 to the desired point of delivery. The conveyor mechanisms are conventional and may be suitably designed for the particular product being carried thereon.

Each conveyor 12, 13, 14 is covered by a grate 15 which has a top surface mounted flush with the top surface of the bed 19. The grates l5 serve to protect the conveyors 12-14 from the pressure of the storage pile and also act as grading elements by refusing to pass particles having bull-1 in excess of the grate openings.

The common problem in such conveyor units is the tendency of the particles to bridge across the grates 15 in a solid bulk pack and thereby reduce or totally eliminate the flow of particles through the grates 15 to the conveyors 12-14. in order to prevent this occurrence, the present invention employs means to drag the particles across the grates 15 so as to supply the conveyors 1244 with a constant supply of particles and also prevent any accumulation of particles on the grates 15.

The supports for the assembly comprise a series of upright posts to securely embedded in the support bed 10 in a Wide circular configuration. Mounted near bed It on each post 16 is a roller 17 supported for rotation about a vertical axis. The rollers 17 abut an outer cylindrical member 18 of a ring generally denoted as 20. An inner cylindrical member 21 is mounted coaxially with respect to member 18 by means of a circular bearing plate 22 which rests on the surface of the support bed 10. The inner cylindrical member 21 has secured to it a series of drag units 23. Each unit 23 comprises a chain of scoop elements 24 which are connected to one another by hinges 25. The outer scoop element 24 is hinged directly to ring 2% Each scoop element is formed from a quarter of a cylinder with the inner end blocked by a quarter of a circle. As the scoops travels, the open end faces the direction of motion. Each drag unit 23 is preferably about 540% longer than the radius of ring 20 so as to insure coverage of the full area Within ring 20. The drag units 23 are spaced along the inner surface of ring 2t) by an arcuate distance slightly greater than their individual links so as to avoid interference between adjacent drag units 23 when they are at their widest arc of travel.

The ring 20 moves in the direction indicated by the arrow 25 in FIGURE 1. In order to provide this motion, two motor units 27 are utilized. Since both units 27 are identical, the same numerals will be used to designate the components of each unit. A motor 23 is suitably mounted on a pedestal 3%. An output sprocket 31 on motor 28 is connected by a chain 32 to a driven sprocket 33 fixed to a transmission shaft 34. Shaft 34 is journalled on a standard including a bar 35 supported at one end by two legs 36 and supported at its remaining end by a pair of perpendicular rollers 37, 33 which roll along the top and inner edges of cylindrical member-18 respectively. The lower end of shaft 34 is provided with a gear 49 which meshes with a chain 41 welded to the outer periphery of the cylindrical member 18. Thus, rotation of the shaft 34 by motor 28 results in rotation of ring 20 on bed about a central vertical axis.

The ring 29 rests on bed 19 by means of bearing plate 22. In order to ease rotation of ring 28, the surface of the bed 10 is initially hardened by application of a commercial hardener. As the hardener sets, graphite is troweled into the surface. For a replacement surface after wear, graphite mixed with epoxy resin is used to build a new surface. In this manner a strong bearing surface is maintained below ring 20.

Since the drag units 23 must pull the particles beyond the pile before they can be dragged across an open portion of a grate 15, a limiting bulkhead must be provided to enclose and define the outer radius of the storage pile. This is accomplished by means of a hood 42 which has a top bevelled flange 4-3 shaped as a frustrum of a cone and secured to the upper end of posts 16. A vertical metal abutment 44 hangs down from the top end of flange 43 to an elevation slightly above the height of a scoop element 24. The lower end of abutment 44 is spaced from ring 20 by a distance equal to the width of a scoop element 24 to insure the free passage of the scoop elements 24 between ring 20 and a projection of abutment 44.

Also mounted on flange 43 is a weighted cloth dust cover 45 which hangs loosely adjacent the inner surface of cylindrical element 21 to seal off the area outside of ring 20 from dust which might be raised by the operation of this device.

Mounted at the center of bed 10 is a conical cover 46 which covers the junction of conveyors 1214 and serves to prevent the drag units 23 from becoming entangled at their inner ends. Also mounted above the grates are triangular covers 47 which prevent material from packing on grates 15 during dumping operations. Covers 47 are fixed to posts 16 and extend through flange 43 and abutment 44 to the conical cover 46.

The foregoing describes the apparatus for an open pile. If an enclosed receptacle is desired, it may be built upward from abutment 43 to any desired height and would also be supported on posts 16.

The operation of the apparatus is best seen in FIGURE 8. As the ring 2% is rotated, the drag units 23 will scrape along bed 19 in an arc tending to cross the axis of ring 21) but is blocked by the central conical cover 46. The scoop elements 24 will ride along the periphery of the storage pile 48 regardless of its diameter. The maximum diameter of pile 48 is fixed by hood 42. Scoop elements 24 will each bring a portion of particles across a grate 15, where it will fall downward to one of the conveyors 12-14. The amount of particles being delivered can be increased by increasing the speed of motors 28 to drag more particles across grates 15. The scoop elements 24 also keep the grates 15 clear of excess particles to thereby insure constant delivery to conveyor 14.

A typical installation is diagrammatically shown in FIGURE 9. Here the particles are fed by a first conveyor 50 to a gate 51 which can selectively divert them to a reversible belt 52 or to a bypass belt 53. Belt 52 can take the particles to either of two storage support beds 54, 55 where the particles are dumped until needed. The beds 54, 55 have cross conveyors 56, 57 respectively and delivery exit conveyors 58, 59 respectively recessed below them. At the. junction of conveyors 58, 59 is a lower final C0111 veyor 60 which runs from a grate 61 to a final delivery hopper 62. In the case of a sawdust operation, hopper 62 might be the intake hopper for a burner.

Particles can then be either stored on the two beds 54, 55 and then fed by conveyors 58, 59 as needed, or can bypass the beds 54, 55 entirely and be dumped through grate 61 directly onto conveyor 6%). By proper manipulation a constant controlled flow of particles can be delivered at hopper 62.

Various modifications may appear evident to one skilled in this art in view of the above teachings. Therefore, only the following claims should limit the scope of the invention.

Having thus described my invention, I claim:

1. In an apparatus for particle transfer from a storage pile, a horizontal support for the pile including recessed conveyors extending outwardly from the pile below the surface of the support, a ring means encircling the pile and rotatably supported on said support for movement about a vertical axis, flexible drag means secured at one end to the inner cylindrical surface of said ring means freely mounted to swing radially with respect to said ring, and drive means operatively connected to said ring means adapted to rotate the ring means about said vertical axis.

2. In an apparatus for particle transfer from a storage pile, a horizontal supporting bed for the pile, conveyor means recessed below the surface of said bed and extending outwardly therefrom, cylindrical ring means encircling the pile and rotatably supported on said bed for movement about a vertical axis, flexible drag means secured to the inner cylindrical surface of said ring means for free radial motion with respect to the axis of said ring means, hood means mounted on said bed in co-axial relation to said ring means slightly above said drag means, said hood means being spaced radially inward from said inner cylindrical surface of said ring means, and drive means operatively connected to said ring means adapted to rotate said ring means about its axis.

3. In an apparatus for particle transfer from a storage pile, a horizontal supporting bed for the pile, conveyor means recessed below the surface of the bed and extending outwardly therefrom to a delivery mechanism, grate means mounted on said bed flush with its upper supporting surface and covering said conveyor means, cylindrical ring means slidably supported on said bed for rotation about a central vertical axis, said ring means encircling the pile, flexible drag means secured to the inner cylindrical surface of said ring means, said drag means being free to move inwardly at its remaining end, hood means fixed to said bed in co-axial relation to said ring means slightly above said drag means, said hood means being spaced radially inward from said ring means, and drive means on said supporting bed operatively engaged with the ring means and adapted to rotate said ring means about said central vertical axis.

4. In an apparatus for particle transfer from a storage pile formed on a horizontal supporting bed having a recessed exit conveyor including a grate covering said conveyor mounted flush with the upper surface of said supporting bed, and entry means mounted above said supporting bed adapted to dump particles onto said pile, a cylindrical ring slidably mounted on said bed, support means on said bed engaged with said ring to position it about a central vertical axis through the pile, a series of flexible drag assemblies spaced about the inner circumference of said ring, each drag assembly including a chain of scoops, one end of said chain being hinged to the inner ring surface, the remaining end of said chain being free to swing radially inward toward said central vertical axis, and variable speed drive means operatively connected to said ring adapted to rotate said ring about said central vertical axis.

5. The apparatus described in claim 4 further including a circular hood fixed above said bed on supports anchored to said bed, said hood being co-axially spaced inwardly of said ring, the lower end of said hood being slightly above said drag assemblies, said hood limiting the outward boundaries of said pile.

No references cited. 

